Study Guide:Ground

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General

Ground is responsible for all movements of aircraft on ground, except the movements on the runway. Ground takes over responsibility for Delivery if he is not online.

Ground

(see the ground chart [which you find here]).

Vienna has three piers with gates and some stands around. From West to East, there are:

  • General Aviation is all the way to the West at Taxiways Q and P.
  • Cargo stands at A91 to A96 and B43 to B69(not included in the Flytampa scenery)
  • Near EX12, there are three rows for small commercial airliners B71 to B92).
  • Pier West (gates C31 to C42) and Pier East (D21 to D29) are next. They are made for M aircraft, with the corner stands C36, C39, D23, D26 and D28) for available for H aircraft too.
  • Pier North or Terminal 3 ("Skylink"), housing gates to the South (F01-F37, odd numbers) and the North F04-F36, even numbers). Heavy gates are north and south of the terminal.
  • F stands including heave stands are marked east of the skyline terminal and are still part of the pier north. They are also used for de-icing during the winter season. These stands are taxi out positions
  • South of Pier North are stands for smaller and budget airliners, most DH8D park there. The positions do not require pushback (E stands).
  • North of Pier North is another row for smaller and budget airliners (H stands).

Taxiways

  • Two parallel taxiways (L and M) run along runway 11/29. Caution: Taxiway L after EX12 is narrower.
  • Runway 16/34 have another two taxiways: D and E. D is somehow shorter, E goes through all the way.
  • An extra taxiway (W) leads from EX2 to EX21.
  • Then there are some taxilanes to access Pier North (TL35, 36 and 37 to the South of the pier, TL40 to the North). TL40 has a blue (south) and an orange (north) variant, which not all sceneries have, so be aware if pilots cannot see it.

Basic principles

The basic principles for Radio Telephony apply:

It is ground's responsibility to direct and monitor ground movements

Start-up clearance

Start-up clearance may be given if you expect the aircraft to depart in a timely manner. (coordinate with GND and TWR accordingly)

Austrian 125, start-up approved.

Push-back clearance

Push-back clearance can be given if no other aircraft is passing behind and the parking position requires push-back.

Austrian 125, push-back approved

Start and Push clearance

Use these two phrases together

Austrian 125, start(-up) and push(-back) approved


If the aircraft does not initiate pushback within an adequate timeframe, you may cancel the pushback clearance:

AUA123 Pushback clearance cancelled, I call you (back).

Thereafter you may clear anyone else to pass behind, and you have to re-issue the clearance later on.

Taxi Instructions

The pilot will conduct startup and pushback. As soon as he is ready for taxi he will call you:

AUA125: AUA125, request taxi.

Depending on the traffic situation you can either clear the A/C directly to the RWY or issue an intermediate clearance:

AUA125, taxi via M hold before EXIT 7.

or

AUA125, taxi to holding point Rwy 16 via L and W.


So, how do you maintain traffic flow at a busy airport?

You may clear an aircraft to an intermediate stopping position: "Taxi via E hold before EX24".

AUA125, Taxi via the Blue Line and E, Hold before EX24.

You may also add a condition to this to keep things moving:

AUA125, Taxi H/P RWY 29 via Blue Line, E, EX24 and EX1, on E behind Company Airbus From the right.

This means: the A/C has to "hold before" (=to stop) in mid way for a condition which you specify.

  • This could be only to "hold short" --> until you tell them to "continue".
  • It could be "behind the A320 from left to right".
  • It could be "follow company A320 taxiing on L".

The "Hold before" argument reduces your workload, as the pilot must now judge if they can meet the conditions given.

Bear in mind that it is the controllers' job to decide on wingtip clearance.

On VATSIM, you sometimes meet pilots who apparently don't have charts and/or lose orientation - especially when it is dark and the scenery is outdated. If a pilot starts sight-seeing, you can tell them to stop ("hold position") and to "expect progressive taxi", and that means: you taxi him step by step, and they are instructed to stop at every step.

When an aircraft is approaching its assigned holding-point (and clear of possible traffic-conflict) a hand-off to next higher position (i.e. TWR) shall be initiated as soon as the aircraft is conflict-free in your area of responsibility. This means, if no other aircraft can be in the way on his way to the runway. Example for LOWW: Suppose, RWY 29 - GND will line up all aircraft on taxiway M facing East. Hand them over to TWR as soon as practibale. Avoid unnecessary intermediate stops of taxiing aircraft.

AUA125 Contact Wien Tower 119,400.

Taxiway configurations

Taxiing with 29-only

With strong westerly wind and after 21:00 local, 29-only is the option. This the option for minimizing conflicts:


29only.jpg

Taxiing with 29-34

When wind is Northwesterly, then departing 29 and arriving 34 is an option.

There may even be departures from 34 in this ground flow configuration. Traffic flow could be as follows:

29-34.jpg

Taxiing with 11-16

Vienna has a local procedure to have quasi-parallel operation of runway 11 and 16. In this configuration, aircraft depart from 16. Arrivals are 11 and 16 depending on traffic and aircraft class (Heavies cannot approach 11 if 16 is open, as go-around paths would cross). Taxiing is somehow complex in this situation:

You could handle the flow like this, which will turn L and M to left-around to minimise conflicts. There is a hot spot at EX23, where outbound and inbound traffic cross. However, departing traffic will be able to see departing on their right hand side, so you can work with conditional clearances ("give way to crossing traffic from D at Exit 23").

11-16.jpg

Taxiing with 29-16

When the wind is low, but southerly, then 29-16 is a good option. This is how you can handle it:

29-16.jpg

  • There is a Noise Abatement procedure after 21:00 local time, which changes runways to 29-only, if wind permits. SIDs after 21:00 might change. Tower changes runways, so expect to be notified of the change.
  • VFR traffic does not necessarily depart or land from the runway in use - enquire from TWR, what to clear, and if TWR or DEL clears. Most likely you will clear him (set the runway in Euroscope) and hand him over to ground as any other IFR flight. Enter the exit route into the flight plan or the text field in the tag.

Ground Traffic Management

Step-by-step clearance

The safest and primary way to achieve safe operations:

AUA251, taxi via E hold before M.
AUA251, taxi via M, hold before Exit 7.
AUA251, taxi via L, hold clear of Exit 9.
AUA251, continue to gate D21 via Exit 9.

Conditional clearance

This provides much more flow, but you have to think in advance. See, which aircraft approach to where and give one of them a conditional clearance to stop some point and give way. Make sure that the condition is clear: a specific intersection, a precise plane from a precise direction, like this:

AUA251, taxi to gate D21 via E, M and Exit 9, On M give way to company A320 from the right.

"Conditional clearance" means: AUA251 is free to taxi until its final clearance limit (D21), but stops inbetween until the condition is met, in this case: another Austrian A320 taxiing (presumably on D) and turning in before him. Then, he is free to continue without instruction. "Hold short" means: You are cleared to your destination, but you should stop inbetween.

Intermediate instructions

Sometimes, you might need to re-clear or stop an A/C:

AUA251, hold position.
AUA251, continue.
AUA251, hold before W, B190 crossing right to left.
AUA251, gate change, taxi to gate F1 via M, EX7, at EX7 behind Swiss A320 crossing right - left.

Progressive Taxi

Some pilots don't know how to taxi, and some don't know where to taxi, and they can drive you mad. To them, you can issue progressive taxi instructions:

Leipzig Air 600, turn next left hold next intersection.
Leipzig Air 600, turn right, on third intersection left and hold.

Example

Consider the following situation:

You are the Ground Controller at Vienna Airport. Runways active are 34 for landing and 29 for departure. DLH6KM has vacated rwy 34 and requests taxi to its parking position. LZB421 is ready for taxi at stand B95.
GND:DLH6KM taxi to stand C40 via taxiway D and L.
DLH6KM:Taxiing to stand C40 via D and L, DLH6KM.
LZB421:Wien ground LZB421 stand B95, ready for taxi.
GND:LZB421, Taxi via L, hold before EX11.
LZB421:via L, hold before EX11.
The aircraft are now both approaching EX11.
LZB421, When clear of the opposite 737, continue EX11 and M to H/P RWY 29.


Of course you have to make sure that this instruction is unambiguous, so there shouldn't be two DLH B737s in the area.

Intersection departure

Even though HIRO (High Intensity Runway Operation) requires pilots to plan certain intersection departures e.g (A3, B4, B10, A10), usage of these intersection should be restricted to cases where a gain in efficiency can be accomplished.

Avoid "over-using" e.g A3, as there is no gain in efficiency to be expected from a 3 aircraft long queue for A3 (TFC congestion on TWY M and L).



Some flights do not need the whole length of their given departure runway so they might request takeoff from an intersection somewhere down the runway. This procedure is called a intersection takeoff. You should only grant this in coordination with Tower and if traffic situation permits. Also at some airports intersections are used to be more flexible in the departure sequence (see section Departure Seperation).

Phraseology to ask an A/C for its ability to make use of an intersection is as follows:

 AUA4CM can you accept B4? 

if answered positively ->

Roger, join B4 (report ready) 


Special Case Northern F stands

As this area is equipped with 3 parallel Taxilines, those being Taxiline 40 Center, Blue Line and Orange Line, it is vital to make use of these Lines in a sensible manner.

  • Taxiline 40 Center is issued to Heavy A/C up to a maximum Wingspan of 68.4 Meters
  • Blue and Orange Line may be issued to two A/C taxiing in parallel up to a maximum Wingspan of 36 Meters. This gives the Controller the ability to essentially double the flow rate in this area as also pushback may be conducted onto either of those lines. Make sure to state this in the Push Clearance accordingly

e.g

 "AUA9LT Start and Push approved - Blue Line" 

Phraseology in this area is as follows:

 "Taxi to Position F08 via the Blue Line" 

or

 "Taxi to Position G26 via Taxiline 40 Center" 

Positions G16, G26 and G36 are used for Heavy A/C and are collocated with their respective F counterparts F16, F26 and F36. Nevertheless they provide greater wingtip clearance.


Swingovers

Another option to make use of this infrastructure is to clear "swingovers".

"AUA9LT Swingover Orange Line continue W to H/P RWY 16"

This procedure is particularly useful to clear e.g the Blue Line for incoming traffic.

Special Situations (High Traffic, Slots, ...)

Intermediate Holding Positions (IHP)

In dynamic and high TFC situations it is advisable to make use of intermediate clearances to keep both your and the pilots flexibility to change route at a maximum. It is therefore suggested to make use of IHPs such as:

  • M2
  • L2
  • Blue 1
  • Orange 1

Nevertheless you should try to keep the A/C moving and avoid unnecessary stops at these positions if they are of no use to your flow management.

Slots

In case the above mentioned slot regulations are in force ground has the responsibility to set up a departure sequence in a way that the aircraft do not miss their slot.

Helicopters

First and foremost, air-taxiing is not done by GND! Permission do so is granted by TWR only in coordination with GND!

Air-taxiing is the Movement of a helicopter / VTOL above the surface of an aerodrome, normally in ground effect and at a ground speed of normally less than 20 KT (37 km/h). Please Note: The actual height may vary, and some helicopters may require air-taxiing above 25 FT (8 m) AGL to reduce ground effect turbulence or provide clearance for cargo sling loads.

OEBXR: request air taxi to Runway 29.
GND: OEBXR, contact TWR 119.400.
OEBXR: Servus Wien Tower, request air taxi to Runway 29 via Exit 13 and M.
TWR: OEBXR, air taxi to Runway 29 via Exit 13 and M. wind 280 deg 5 knots
OEBXR: air taxi to Runway 29 via M.

Opposite runway operations

At some austrian airports it is very common to use opposite runway configurations (departure and arrival runway are opposite to each other). In these situations it can happen very fast that you have two aircraft facing each other nose to nose. Special attention should be paid to avoid this situation.

Mind the wingtip: Size matters to GND controllers

As GND controller, you have to watch out for the size of an aircraft. You have two indications for the aircraft size in Euroscope: The Letter "L/M/H/S" in the flight strip, and the precise aircraft type in the departure list or tag - an abbreviation which you might need to google, but you will learn over time.

  • Light aircraft (L) need to go to stands, not to docks (you won't want to dock a Cessna, will you?). But "light" is not "light" - on some GAC aprons the aircraft has to be really light, especially when it comes to grass surface. Watch out to the aircraft type.
  • Medium aircraft have a different trouble: Some of them (like the Beech 99, the Dash or the Avro RJ are medium, but they need stands. Others, not much bigger, like the Fokker 70 or 100, can dock at the gate, whereas others (like the A319), only a little bigger, usually dock. In doubt: ask the pilot. The medium category goes up to the most-frequent cruisers A320 and B737.
  • Heavy aircraft are (almost) everything above: A330, B767 and B747, the MD11 and the new B787. They almost exclusively dock, but there is another risk: Not all docks are suitable for heavies - ground charts tell you more. Check this chart [1] to verify where you can park which A/C.
  • Superheavy aircraft e.g The A380 - which is parked at F35, D27 or H98.


as hint for parking, you could use follow flow Chart:

Parking Flow chart.jpg

Additional Information

For further information relating to traffic flow management on ground in different configurations, please refer to: ATMM guide


If you really want to study hard, then read the relevant sections for GND in the official radio telephony guide from Austrocontrol.

A really good index (and much more orderly is here at Eurocontrol.


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